Here we go again, says health journalism watchdog Gary Schwitzer of Health News Review, citing headlines that blare claims like “Coffee may reduce stroke risk!”

These media headlines introduced findings from a new study in which women who drank more than a cup of coffee a day had a 22% to 25% lower risk of stroke than those who drank less, according to Swedish researchers.

Their research was published in Stroke: Journal of the American Heart Association. Stroke is the third leading cause of death in North America, behind heart disease and cancer.

But Gary Schwitzer explains that although this was a big study (over 34,000 women ages 49-83, followed for an average of 10 years), it was only an observational study that can’t prove cause and effect. Continue reading →